Improvement in helical springs



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WILLIAM RHODA NICHOLS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR NICHOLS, PIOKERING & 00., 0F SAME PLACE.

Letters Patent No. 102,421, dated April 26, 1870.

IMPROVEMENT IN HELICAL SPRING-S.

The Schedule referredto in these Letters Patent and making pazt of the same.

I, WiLLIAM RHODA NICHOLS, of Philadelphia, county of Philadelphia, State of Pennsylvania, have invented an Improved Helical Spring for "Railroad Cars, of which the following is a specification.

. Nature and Object of the Invention.

Description of the Accompanying Drawing. Figure 1 is a vertical section of my improved helical spring for railroad cars.

Figure 2, the same as it appears when compressed to its utmost limit.

Figure 3, an exterior view of the spring.

General Description.

It will be seen, on reference to the drawing, that my improved spring consists of a flanged bar, A, of steel, coiled in the form of a helix, the flange a being on the exterior of the barand at the upper edge of the same,

and the coils being so arranged that while one is within, it shall not be in contact with the other, while'the flanges are at all times free from contact with each other and with any other part of the spring, unless the latter be compressed to its utmost limits, as shown in fig. 2, a point to which the spring has rarely, if ever, to be compressed.

I am aware that helical springs have been" made both of plain flat bars of steel and of bars with a flange on each edge; but I have found, ait-er repeated tests, that the most effective helical spring can be produced by boiling a bar with single external flange situated at the upper edge of the coil, providing the folds are arrangedvertically and parallel with each other, as shown in the drawing.

' While my improved helical spring may be made somewhat higher than those of ordinary construction, owing to the presence of the external flanges a, the latter imparta lateral stability to the spring, without impairing its elastic properties.

Claim.

A helical spring, composed of vertical and parallel coils, with upper external flange, as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

WILLIAM RHODA NICHOLS. Witnesses:

P. B. J onus, CHAS. E. PANCOAS'L' 

